Joe Biden and Kamala Harris started off as rivals, both wanting to run for president for the Democratic Party.

At the end of June 2019, during the first debate, they got into an argument. California Senator Harris criticized the former vice president for his policies during the 1970s. At the time, Biden was a senator for the state of Delaware. He had been working with US senators who wanted to prevent the integration of Black and white schoolchildren, said Harris — and that she was one of those pupils.

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Joe Biden defended himself by saying he was only against mandated "bussing." The term refers to the practice of driving black children to selected schools that were usually located in richer, white residential areas. Harris, who rode one of these buses to school as a child and credits her education for her success, stated: "Had I been a United States senator at that time, I would have been completely on the other side of the aisle."

The clash was extensively covered by the US media. But in the end, Harris herself pointed out that it had just been a disagreement on one issue. It did not prevent Joe Biden from choosing Kamala Harris as his running mate. On the contrary, he showed that criticism is welcome and, unlike US President Donald Trump, he does not demand blind loyalty.

Heading in the same direction

Although Harris and Biden don't have much in common at first glance, they are — in terms of their political agenda — a harmonious duo. Their main topics are the economy, the environment, education and social justice. With enough distance to radical and progressive ideas on the left and the conservative Republicans on the right, they are likely to appeal to a large section of the population.

Many Democrats already liked the Biden/Harris combination before the California senator dropped out of the presidential race. Representative Lacy Clay from Missouri, for example, told the news outlet "Politico" in May 2019 that "that would be a dream ticket!"

And he was not alone with his opinion. Not many could imagine a Black and Asian woman succeeding as a presidential candidate, but could see her as an ideal counterweight to Biden. On the other hand, many voters were not enthusiastic about Biden, but now with Harris by his side, views are shifting.

Balance is key

The two Democrats represent both experience and tradition with 77-year-old Biden and the often missing perspective of a non-white woman in the shape of the 55-year-old Harris, whose parents were immigrants from Jamaica and India.

Two mentalities come together as well. Biden spent his childhood and youth in Pennsylvania and Delaware on the East Coast, as the child of a white family who struggled to stay part of the middle class. Harris grew up on the West Coast in California, where her parents had met during protests against the Vietnam War.

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Both studied law, but whereas Biden entered politics early and won a Senate seat at the age of 29, Harris worked her way up as a lawyer and only swapped her position as Attorney General in California for a seat in the US Senate three years ago.

By then Biden and Harris' paths had already crossed. Joe Biden's son, Beau, was Attorney General in Delaware, and in 2011 he worked with Harris to hold banks accountable in the wake of the housing crisis. Beau Biden died of a brain tumor in 2015, but his friendship with Harris and his high opinion of the lawyer from California influenced Joe Biden's decision to pick her as his vice president.

Kamala Harris has shown that she is quick on her feet in debates and is not easily intimidated by her opponents. In 2018, she received a lot of attention for her thorough questioning of the then Supreme Court nominee Brett Kavanaugh during his confirmation hearing. Her job, among other things, will be to have Joe Biden's back and fend off criticism.

By trusting Harris, Biden has opened a door that might stay open for minorities in future. He is fully aware of the symbolism of his choice for vice president. On the day of the announcement, Joe Biden tweeted: "This morning, little girls woke up across this nation — especially Black and Brown girls who so often may feel overlooked and undervalued in our society — potentially seeing themselves in a new way: As the stuff of Presidents and Vice Presidents."